* {
    margin: 0;
    padding: 0;
}

.content {
    width: 640px;
    height: 640px;
    margin: 30px auto;
    position: relative;
}

.btn {
    width: 100%;
    height: 100%;
    position: absolute;
    left: 0;
    top: 0;
    background-color: rgba(0, 0, 0, 0.3);
    z-index: 2;
}

.btn button {
    background: none;
    border: none;
    background-size: 100% 100%;
    cursor: pointer;
    outline: none;
    position: absolute;
    left: 50%;
    top: 50%;
}

.startBtn button {
    width: 200px;
    height: 80px;
    background-image: url(../images/startGame.png);
    margin-left: -100px;
    margin-top: -40px;
}

.pauseBtn {
    display: none;
}

.pauseBtn button {
    width: 70px;
    height: 70px;
    background-image: url(../images/start.png);
    margin-left: -35px;
    margin-top: -35px;
}


/* snakeWrap */

#snakeWrap {
    width: 600px;
    height: 600px;
    background: #225675;
    border: 20px solid #7dd9ff;
    position: relative;
}

.snakeHead {
    background-image: url(../images/snakeHead.png);
    background-size: cover;
}

.snakeBody {
    background-image: url(../images/snakeBody.png);
    background-size: cover;
    /* background-color: #9ddbb1; */
    /* border-radius: 50%; */
}

.food {
    background-image: url(../images/apple2.png);
    background-size: cover;
}


/* 计分器 */

.score {
    width: 240px;
    height: 240px;
    position: fixed;
    left: 1110px;
    top: 30px;
}

#yourScore {
    width: 200px;
    height: 200px;
    background: #225675;
    border: 20px solid #7dd9ff;
}

.startScore {
    color: white;
    font-weight: 600;
    font-size: 75px;
    text-align: center;
    background-color: rgba(0, 0, 0, 0.3);
}

.yourScore {
    display: none;
}

.yourScore {
    line-height: 100px;
    font-size: 50px;
    color: white;
    text-align: center;
}


/* 速度控制按钮 */

.speed {
    width: 240px;
    height: 100px;
    position: fixed;
    left: 1110px;
    top: 290px;
}

.speed button {
    width: 60px;
    height: 40px;
    font-size: 20px;
    line-height: 38px;
    font-weight: 600;
    background-color: #225675;
    color: white;
    border: none;
}

.leftSpeed {
    float: left;
}

.rightSpeed {
    float: right;
}

.clear {
    clear: both;
}

.centerSpeed {
    margin-left: 30px;
}